Corner connector for tubular members

ABSTRACT

A fitting for interconnecting generally square-shaped tubular members wherein the fitting has projecting arms which are ensleeved within the tubular members, the arms being structured to provide a ledge at the base or root thereof to develop stabilization of the thus interconnected tubular members in addition to the use of any securing bolt.

United States Patent Gutner Dec. 17, 1974 [5 1 CORNER CONNECTOR FOR TUBULAR 3,545,123 12/1970 Muller 287/54 A MEMBERS FOREIGN PATENTS OR APPLICATIONS [76] Inventor: Kenneth H. Gutner, 3285 Dato, 687,592 6/1964 Canada 287/54 A Highland Park, 111. 60035 815,767 6/1969 Canada 287/54 A 22 Filed: Aug. 31, 1970 Appl. No; 68,403

Primary ExaminerJordan Franklin Assistant Examiner-Wayne L. Shedd Attorney, Agent, or FirmDawson, Tilton, Fallon & Lungmus [57] ABSTRACT A fitting for interconnecting generally square-shaped tubular members wherein the fitting has projecting arms which are ensleeved within the tubular members, the arms being structured to provide a ledge at the base or root thereof to develop stabilization of the thus interconnected tubular members in addition to the use of any securing bolt.

4 Claims, 12 Drawing Figures PATENTE'U in 1 Y I914 3; 864,831

sum 1 mg g KENNETH H GUTNER PATENTEL 1 H974 3,854,831

sumzu g INVENTOR: KENNETH H. GUTNER ATT'YS PATENTEB 55E 1 7 I974 3, 8 4, 83 l saw 3 a? 4 KLNNLTH H, GU'INKR ATT'YS CORNER CONNECTOR FOR TUBULAR MEMBERS BACKGROUND OF THE INVENTION This invention relates to fittings for interconnecting furniture frames such as are found in coffee tables, partitions and the like. For example, a coffee table may be made up' of a glass top and four legs interconnected by means of two side pieces and two stretcher pieces. The table top support unit has the various elements connected at top corners by means of a fitting to which the instant invention is directed.

In the prior art, the most usual method of interconnecting metal legs, sides, and stretc-hers was achieved through welding. Following the welding, it was necessary to clean the interconnected members, particularly at the area of union, filing the same, and then providing a large tank to plate the assembly. Attempts have been made to provideslip-on fittings for this assembly in the nature of tees and the like, but these have provided problems .of reliable securement. It will be appreciated that the inadvertent disconnection of sides from legs when the interconnected sides and legs are designed to support a plate glass table top is not only undesirable,

but potentially dangerous, On the other hand, the connection must be readily achieved during set-up in the home or office so that elaborate or difficult to achieve securement is equally undesirable.

SUMMARY OF INVENTION lization is derived from constructing and dimensioning integral arm portions so as to snugly fit within the ensleeved tubular members.

DETAILED DESCRIPTION The invention is described in conjunction with the accompanying drawings, in which: FIG. 1 is a perspective view of one embodiment of the drawing and the particular application shown is a coffee table;

FIG. 2 is an enlarged fragmentary perspective view partially in exploded form to show the fitting used in the corners of the supporting-structure of FIG. 1';

FIG. 3 is a sectional view such as would be seen along the sight line 3.3 of FIG. 2, but with the boltin assembled position; I

FIG. 4 is a fragmentary perspective view of a modified fitting embodying teachings of the invention;

FIG. 5 is a fragmentary perspective view of another modified fitting of the invention;

FIG. 6 is a perspective fragmentary view of another modification;

FIG. 7 is another fragmentary perspective view of a yet further modified form of the invention;

FIG. 8 is an exploded perspective fragmentary view of the modification seen in FIG. 7;

FIG. 9 is a fragmentary sectional view of the 'structure encircled in FIG. 7;

FIG. 10 is a perspective view ofa table equipped with bottom corner fittings made according to another modification of the instant invention;

FIG. 11 is an'enlarged fragmentary sectional .view of one bottom corner of the structure of FIG. 10, and which is encircled in FIG. 10; and

FIG. 12 is a fragmentary perspective exploded view of the encircled portion of FIG. 10.

In the illustration given, the numeral 10 designates generally a coffee table which is seen to include a supporting structure generally designated 11, and a glass top 12. Because of the glass top 12, it is possible to see the supporting structure which creates an aesthetic impression in the eye of the viewer, and therefore it is desirable that the connective portions not only be secure, but ornamental. For this purpose I provide corner connectors as at 13 (see particularly FIGS. 2 and 3). Each cornerconnector serves to interconnect a stretcher, as at 14 or 15 (as the case maybe), with a side member 16 or 17 and a leg 18,19, 20, or 21.

Referring now to FIG. 2, the leg 18 is seen to be inter- .arm 24, as can be readily appreciated froma consideration of FIG. 3, projects laterallyfrom the fitting 13 a v 25 are identical, differing only in disposition relative'to spaced distance below the top wall 22 provided by shoulder 24a. The distance provided by the shoulder- 24a corresponds to the gauge of the tubular members (in the illustration shown in FIG.',3, the side members 17 and 14). In the illustration given, the arms 24 and the corner portion of the fitting l3 and'the tubular leg '18..Each arm 24 or 25, as the case may be, is equipped with a top wall of its own, as at 26, and depending side walls as at 27. The side walls 27 have at their base or root a ledge part, as at 28, which has a height dimension corresponding to the internal height dimension of the tubular member 17. The remaining portion of each of the side .walls 27 is relieved, as at 29, so as to have a lesser height dimension.

To further'secure the tubularmembers (as at 17) to the fitting 13, I employ a bolt 30 which is received within a tapped bore 31' provided in a givenarm 24. In the illustration given, the bolt has a raised head portion, as at 32, which engages a mating bore or opening 3-3 in the bottom wall of the tubular side member-17. Thus,

- the bolt 30 and the ledge 28 cooperate to stabilize and fix the tubular member 17 relative to the fitting 13. It will be appreciated that in certain instances it may be desirable to employ other forms of bolts. However, the bolt illustrated is advantageous in that, as'it isun-,

threaded from the bore 31 and thus extends further into the opening 33, it serves to cinch or urge the tubular member 17 against the shoulder 24a. For this purpose the head portion 32 is tapered as at 32' at an angle of about 10 I maintain the distance between the adjacent edge of the opening 33 and the end of the member 17 at a predetermined value so that this cinching action can occur.

I The fitting 13 is equipped with a depending stub or leg34 which fits within the tubular member 18. A press fit is advantageously achieved through the use of ribs 35 which are vertically elongated and provided on at least one, and preferably all, of the four faces of the de pending leg 34. If desired, an end cap 36' may be inserted into the hollow leg 34. The cap 36 may serve an additional locking function by virtue of the head portion 36a projecting laterally outwardly of the stub 34, particularly since the stub 34 is tapered downwardly. The ribs 35 are stepped, as at 35a, intermediate their ends, thus facilitating insertion of the leg 34 into the tubular member 18.

Turning now to the second sheet of the drawings, other variations of the basic fitting can be seen. In FIG. 4 I provide a fitting which is advantageously employable for book shelves whereby a lower leg 134 is provided integral with the fitting 113, as are laterally extending arms 124 and 125. Additionally, I provide an upwardly projecting leg as at 137, this again being integral with the fitting 113 and being substantially identical with the leg 134. v

In FIG. 5 I provide a fitting 213 which differs from the fitting of FIG. 2 in having a third arm, as at 238, to accompany the arms 224 and 225. As such, the fitting 213, when equipped with the depending leg 234, is especially advantageous in use of such as couches, settees, and office furniture in general, whereby modular depending leg 334. The structures of each of the com-- ponent portions is the same as has been previously described, but, here, the arms 324 and 325 are disposed at an angle of l80 relative to each other as contrasted to the 90? disposition shown and described in connection with the illustration of the invention in FIG. 2.-

In the operation of the inventive fitting as illustrated, for example, in FIG. 6, the first step is to install the bolts 330 into the bores 331. It will be noted in FIG. 6, which has been partially broken away, that the bore 331 is defined by a frusto-conical formation 339 which is integral with the arm 325. The formation 339 is advantageously rigiditied by aligned opposed ribs 340 which extend between the formation 339 and the side walls 327 of the arm 325. It will be appreciated that this same construction is employed on the other variations of the fitting depicted herein. Further, the invention contemplates other variations within the range of two to six projections, viz., arms and legs. For example, four arms and two legs may be employed in a given installation.

After the bolts 330 have been threaded substantially into the formation 339 to the extent that the arm 325 is fully insertable into the side member 317 each bolt 330 is unscrewed, i.e., retracted from its threadable receipt within the formation 339, to engage the wall of the opening in the side member 17 (as at 33 relative to the showing in FIG. 3). This provides an advantageous tightening action on the side member 317, the tightening being achieved under guided and stabilized conditions by virtue of the previously referred toledge as at 328.

To complete the assembly, a second arm 324 is installed in an associated side member or stretcher, as at 317a in FIG. 6, following the same procedure as outlined above relative to the arm 325. The leg 318 is then installed.

It will be appreciated that the order of installation may be varied, depending upon the particular installations. The stub leg 334, provided as an integral part of the fitting, is downwardly tapered for ready receipt within the leg member 318. Further, as pointed out previously, the side walls of the stub leg 334 adjacent the leg root are equipped with ribs 335. In one embodiment of the invention, the length of the stub leg 334 is 4 l/2 inches, and the length of the ribs 335 is 7/16 inches. The upper half of each rib, as at 341, has a height above the stub leg surface of 0.014 inch, while the lowerhalf of the rib, as at 342, has a height of about 0.012 inch. Thus, considering ribs on both sides, I have a stepped portion of the order of 0.004 inch. This, in combination with the taper on the stub leg 334 and hence the ribs 335 permits a quick and tight installation of the leg member 318 on the stub leg 334. The relatively limited surface of the ribs can, if effect, be-compressed or shaved when pressure is exerted on the fitting 313 to force it into an associated leg member 318. Thus, I have provided a tight interlock between adjoining members at each corner. It will be noted in FIG. 6 that the ledge 328 associated with the arm 324 is in close proximity with the rib portions 341a. In this fashion I insure that two interconnected members are stabilized and supported immediately adjacent the roots of stub 'arms or legs (as the case may be), while maintained in orthogonal relation. In the specific embodiment illustrated for use with a 1 inch nominal dimension square tube, the length of the ledge 28 is of the order of about l/8 inch to about 3/8 inches and, optimally, 1/4 inch. Further, for a 1 inch square tube which has a wall thickness of the order of 0.048 inch (18 gauge), the height of the tapered'raised head portion 313 is also of the order of 0.048 inch. I

In the illustration given on the third sheet of drawings, a modified form of the invention isseen wherein the corner. fitting 413 (see particularly FIG. 8) has flush top and side surfaces so as to accommodate the provision of amiter joint. Thus, the side member 417 abuts the stretcher 414 along the top surface -of the fitting 413 as can be appreciated from a consideration of FIG. 7. This is in contrast to the abutment of the side member 17 with a shoulder 24a provided on the corner fitting 13 as seen in FIG. 3.

To complete the miter joint, the tubular member ,418, which normally constitutes the vertical portion of I the arrangement, is also arranged and constructed to abut the side member 417 and the stretcher 4.14. The

tubular member 418 is ensleeved over the leg 434,

The three-way miter joint is achieved by providing each one of the elements 414, 417, and 418 with two end edges, as at 411 and 422 relative to stretcher 414, that are perpendicular to the length of the element. The other two end edges, as at 443 and 444, are inclined at an angle of 45 relative to the length of the stretcher, or, for that matter, the other elements 417 and 418. In this fashion I provide a flush joint characterized by a single visible line of union (as from above) in contrast to the arrangment depicted in FIG. 2.

Turning now to the fourth sheet of drawings, a table is generally designated by the numeral 510, and is seen to differ essentially from that depicted in FIG. 1 through the provision of bottom horizontally disposed elements as at 545, 546, 547, and 548. Suitable bottom corner fittings, as at 549 (see FIGS. 11 and 12) are provided to connect the generally vertically extending ele-' ments of the table with the aforementioned horizontally disposed elements 545548. For example, one of the vertically extending elements or legs 518 is seen to be ensleeved over a leg part 550 of the corner fitting 549. The leg part 550 is equipped with stepped ribs as at 551 (see particularly FIG. 12). I find in certain instances that the stepped ribs may be omitted, particularly when the leg is upstanding as in the instance of the construction see in FIG. 4 relative to the upwardly projecting leg 137. In some measure, this provision or absence of ribbingis dictated by the care in design manufacture and the intended usage.

Additional stabilization of the connections between the generally orthogonally related elements is provided through the provision of integral tabs as at 553 and 554 on the generally horizontally disposed integral arm portion 555 and 556 (see FIG. 12). Normally, I prefer to construct the tabs 553 and 554 of a height slightly less than the height of the associated arm at the root or base thereof, i.e., the height of the ledge 557. If, however, this dimensional arrangment is not followed precisely, there will be a further locking action afforded between the tab 553 of the arm portion 555 and the horizontally nated 340.

In this embodiment of the invention, the screws, as at 558, are inserted in a fashion which might be considered the reverse of the installation in the previous embodiments of the invention. In other words, the head of the screw 558 is received within a coutersunk portion 559 of the associated arm 555, and the screw is retracted after the element 545 has been ensleeved over the arm portion 555 so as to be received within the opening 560. Thus, for the important base portions of the table 510, I provide a further advantageous stabilization. Additionally, the screw head is flush and thus does not show.

I claim:

1. In combination, a fitting for interconnecting tubular members of generally square cross-section, comprising a unitary body having at least two integral projections extending away therefromand adapted to be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said one arm being reduced adjacent the end of said arm, said arm being equipped with a tappedbore for receiving a bolt to fix said associated tubular member relative to a given arm, a bolt and tubular member, said bolt having a generally square cross-section, comprising a unitary body having at least two integral projections extending away therefrom and adapted to'be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said one arm being reduced adjacent the end of said arm, said arm being equipped with a tapped bore for receiving a bolt to fix said associated tubular member relative to a given arm, said fitting being equipped with a generally non-resilient stub leg orthogonally related to said arm, said leg being tapered in proceeding away from said body and being generally square in transverse section, at least one of the faces of said stub leg being equipped with stepped rib means extending longitudinally of said stub leg and positioned adjacent the root of said stub leg.

3. A fitting for interconnecting tubular members of generally square cross-section, comprising a unitary body having at least two integral projections extending away therfrom and adapted to be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said one arm equipped with a tapped bore for receiving a bolt .to fix said associated tubular member relative to a given arm, said fitting being equipped with astub leg orthogonally related to said projections, each of said projections additionally being equipped with a relatively elongated tab spaced from the root thereof and with the tab length extending in a direction generally parallel with the length of said stub leg whereby additional stabilization of the connection of said fitting with a tubular member is achieved for usage of the said fitting as a bottom corner fitting.

4. A fitting for interconnecting tubular members of generally square cross-section, comprising a unitary body having at least two integral projections extending away therefrom and adapted to be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said'one arm being reduced adjacent the end of said arm, said arm being equipped with a tapped bore for receiving a bolt to fit said associated tubular member relative to a given arm, said arm being equipped with a tab-like element provided at the end thereof remote from said body and'extending generallyparallel to said tapped bore. 

1. In combination, a fitting for interconnecting tubular members of generally square cross-section, comprising a unitary body having at least two integral projections extending away therefrom and adapted to be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said one arm being reduced adjacent the end of said arm, said arm being equipped with a tapped bore for receiving a bolt to fix said associated tubular member relative to a given arm, a bolt and tubular member, said bolt having a raised head portion operative upon withdrawal to engage an opening in said tubular member to cinch said tubular member in place on said fitting.
 2. A fitting for interconnecting tubular members of generally square cross-section, comprising a unitary body having at least two integral projections extending away therefrom and adapted to be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said one arm being reduced adjacent the end of said arm, said arm being equipped with a tapped bore for receiving a bolt to fix said associated tubular member relative to a given arm, said fitting being equipped with a generally non-resilient stub leg orthogonally related to said arm, said leg being tapered in proceeding away from said body and being generally square in transverse section, at least one of the faces of said stub leg being equipped with stepped rib means extending longitudinally of said stub leg and positioned adjacent the root of said stub leg.
 3. A fitting for interconnecting tubular members of generally square cross-section, comprising a unitary body having at least two integral projections extending away therfrom and adapted to be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said one arm equipped with a tapped bore for receiving a bolt to fix said associated tubular member relative to a given arm, said fitting being equipped with a stub leg orthogonally related to said projections, each of said projections additionally being equipped with a relatively elongated tab spaced from the root thereof and with the tab length extending in a direction generally parallel with the length of said stub leg whereby additional stabilization of the connection of said fitting with a tubular member is achieved for usage of the said fitting as a bottom corner fitting.
 4. A fitting for interconnecting tubular members of generally square cross-section, comprising a unitary body having at least two integral projections extending away therefrom and adapted to be ensleeved within a tubular member, at least one projection being an arm having, at its root, cross-sectional dimensions sized to snugly fit said arm to its associated tubular member, the height dimension of said one arm being reduced adjacent the end of said arm, said arm being equipped with a tapped bore for receiving a bolt to fit said associated tubular member relative to a given arm, said arm being equipped with a tab-like element provided at the end thereof remote from said body and extending generally parallel to said tapped bore. 